A great many methods and substances exist to fight fires. When dealing with fires aboard aircraft, buses, trains, etc., large amounts of water are generally not available and portable containers of fire suppression chemicals are carried. These containers are usually filled with CO.sub.2 or Halon compounds (for example, bromochlorodifluoromethane or bromotrifluoromethane). Their effectiveness depends upon the type of fire which is to be suppressed. For example: water, CO.sub.2, and some dry chemicals are effective on burning wood and paper fires (Class "A"). Halon compounds are suitable for use on fires caused by flammable fluids (Class "A" and Class "B"), and electrical origin fires (Class "C").
The instant invention is primarily concerned with extinguishers using fire suppression chemicals such as Halon compounds. For example, Halon compounds are the principal fire suppression chemicals used in aircraft jet engine nacelles, APU installations, and selected cargo compartments as well as other designated high-fire-risk areas. Unfortunately, due to the high cost and weight of fixed suppression system installations, there are numerous cargo compartments and other inaccessible areas of the aircraft which are not so equipped.
In those areas which are accessible, such as the cabin proper, lavatories, and galleys, etc., fire protection depends upon the use of small, limited-capacity, hand-held extinguishers. An improvement to the hand-held-type extinguisher is disclosed in Applicant's U.S. Pat. No. 4,420,047, "Stowable Fire Suppression System for Aircraft Cabins and the Like". Here, a portable cart containing a tank filled with foam generating chemical is connectable to the aircraft's water supply system to provide fire suppressing foam. Thus, the limited capacity problem is solved.
For the aforementioned inaccessible compartments and areas, it would be very desirable to have the capability of "flooding" them with Halon compounds, thereby providing the most effective fire suppression available. Tackling this problem is U.S. Pat. No. 3,972,373, "Fire Extinguisher System for a Vehicle" by K. B. Nichols, et al. Nichols, et al. disclose a system wherein a hand-held fire extinguisher stored within the passenger compartment of a motor home can be connected from the exterior thereof to a manifold within the engine compartment to fight a fire therein. Such a system is unsuitable for use on an aircraft inflight since the fire extinguisher is connected to the engine compartment from an external connection and not from within the passenger compartment. Additionally, there is no disclosure of a long-term storage fluid isolation system, and means to precisely regulate the delivery of the fire suppression chemical, both of which are highly desirable.
Also of interest is U.S. patent application Ser. No. 665,406, Fire Suppression System For an Aircraft, by W. A. Bruensicke, herein incorporated by reference. This fire suppression system includes a plurality of ducts coupling a plurality of subcompartments to the passage compartment. Each duct has first and second ends with the first end terminating in a first disconnect valve half accessible from the main cabin compartment. The second ends of the ducts terminate in nozzle assemblies within the subcompartment adapted to discharge the fire suppression chemical therein.
A portable unit having a tank filled with a fire suppression chemical is provided which is moveable within the main compartment. This unit has a length of flexible hose coupled to the tank and terminates in a nozzle assembly to which is mounted a second disconnect valve half, connectable to the first disconnect valve half attached to the ducts. In addition, an actuation means incorporated in the nozzle assembly provides flow rate control.
Thus, when a fire in a subcompartment occurs, the portable unit is moved to the location of the first disconnect valve half of the duct connected to that subcompartment, wherein the second disconnect valve half is coupled to the first half so that pressurized fire suppression chemical can be injected into the subcompartment.
One of the outstanding features of this system is that fires within accessible subcompartments, such as lavatories, can be reached without opening a door. This is a significant advantage when in confined spaces such as found on aircraft. The typical approach in a building wherein firemen use axes to break through walls, doors, and ceilings to gain access to the fire, creates serious problems on an aircraft. The most significant is that upon opening or breaking through the wall, the cabin will be immediately filled with smoke, causing severe discomfort and sometimes panic among the passengers. In one actual flight, many passengers were overcome by fumes and died. Thus, being able to reach a fire without opening a door or access panel is a significant advantage.
While this system provides a method for reaching both accessible and inaccessible areas on board the aircraft, it does require that specialized ducting be installed therein. This adds weight and, of course, costs in manufacturing the aircraft.
Therefore, it is a primary object of the subject invention to provide a fire suppression system, wherein both accessible and inaccessible compartments aboard an aircraft can be provided with effective fire suppression chemicals.
It is another object of the subject invention to provide a fire suppression system that can provide fire suppression chemicals to both accessible and inaccessible compartments using a single source of fire suppression chemical.
It is a further object of the subject invention to provide a portable fire suppression system which can be moved throughout the main compartment of the aircraft to fight localized fires therein, as well as those in inaccessible areas above and below the main compartment.
It is a still further object of the subject invention to provide a fire suppression system that can provide fire suppression chemicals to both accessible and inaccessible compartments using a single source of fire suppression chemical and which does not require the incorporation of dedicated ducting within the aircraft.